Electrical coil assembly



April 11, 1967 D. L. VAN ERDEN 3,314,032

ELECTRICAL COIL ASSEMBLY Filed Sept. 8, 1964 01- VAN EEDEN BY 0&5:

ATTORNEY \NVENTOE United States Patent ()filice 3,314,032 Patented Apr. 11, 1967 3,314,032 ELECTRICAL COIL ASSEMBLY Donald L. Van Erden, Bellwood, 111., assignor to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Filed Sept. 8, 1964, Ser. No. 394,954 4 Claims. (Cl. 336198) This invention relates to an electrical coil assembly, and more particularly to a mounting for an electrical coil.

An object of the invention is to electrical coil assembly.

Another object of the invention is to provide an improved mounting structure for supporting an electrical coil.

A coil mounting structure illustrating certain aspects of the invention may include a molded dielectric bobbin having a cylindrical tubular hub on which the coil is wound and which is provided with a plurality of lugs extending inwardly from the inner surface of the hub adjacent one end thereof. A soft-iron cylindrical core is positioned within the bobbin hub and has a rabbeted end provide an improved portion providing a section of reduced diameter which is disposed between the lugs of the bobbin and forms an annular shoulder on the core that rests on the lugs of the bobbin. The end surface of the core is flush with the end surface of the bobbin and both surfaces abut a soft iron pole piece. The threaded shank of a headed machine screw passes through an aperture in the pole piece and engages a threaded aperture in the core to attach the core and the bobbin securely to the pole piece.

In a second embodiment of the invention, the core is modified to provide a second cylindrical section of smaller diameter which extends beyond the first reduced end section of the core and is pressed into an aperture in the pole piece and is securely held thereby to effect the attachment of the core and the bobbin to the pole piece.

Other objects, advantages and novel aspects of the invention will become apparent upon consideration of the following detailed description, in conjunction with the accompanying drawings, in which:

FIG. 1 is a side elevational view of an electrical coil structure illustrating one embodiment of the invention;

FIG. 2 is an enlarged fragmentary vertical sectional view of the coil structure; I

FIG. 3 is an end view of the bobbin and core portion of the induction coil structure looking in the direction indicated by the arrows 33 on FIG. 2;

FIG. 4 is a fragmentary perspective view of the rab- 'beted end of the core;

FIG. 5 is a fragmentary perspective view of the coil bobbin showing the lugs formed on the inner portion thereof;

FIG. 6 is an enlarged fragmentary vertical sectional view of a portion of a coil structure disclosing another embodiment of the invention; and

FIG. 7 is a fragmentary perspective view of an end portion of the core shown in FIG. 6.

Referring to the drawings, one embodiment of the invention as disclosed in FIGS. 15 comprises a molded bobbin 10 having a cylindrical tubular hub 12 and heads 14 and 15 at opposite ends thereof. Extending radially inwardly from the inner surface of one end of the tubular hub 12 adjacent the head 15 thereof are four lugs 18 which [are disposed in angularly spaced relation to each other and are provided with flat surfaces 20 extending parallel to the axis of the hub and transversely disposed shoulder-forming surfaces 22.

The partially square and circular opening through the hub 12 between the projecting lugs 18 permits the placement of a plurality of the bobbins on an arbor having a similar cross-sectional contour for the simultaneous winding of coils 23 onto the bobbin in a coil winding machine.

A cylindrical core 24 of soft iron is positioned within the tubular hub 12 of the bobbin with the upper portion thereof extending slightly beyond the bobbin. The lower end portion of the core 24 is rabbeted at 26 (FIG. 4) to provide a section 27 of reduced diameter and an .mnul-ar shoulder 28. The shoulder 28 of the core rests on the surfaces 22 of the lugs 18 and the reduced section 27 of the core fits between the lugs with the bottom surface 30 of the core substantially flush with the lower end surface of the bobbin 10.

A pole piece 32 of soft iron abuts the end surface 30 of the core 24 and the end surface of the bobbin 10 and is secured to the core by a headed screw 34. The threaded shank of the screw passes through an aperture 36 in the pole piece and engages a threaded hole 38 in the core and secures the core 24 to the pole piece 32, and the core 24 in turn secures the bobbin 12 and the coil 23 to the pole piece. The pole piece 32 selected for purposes of disclosure and as viewed in FIG. 1 is L shaped and has a portion 40 disposed parallel to the axis of the coil 23 and the core 24. An armature 42 is pivoted to the pole piece and cooperates therewith and with the core to form :a path for the magnetic flux of the coil 23 when the coil is energized.

In the modified embodiment of the invention as disclosed in FIGS. 6 and 7, the core 124 has a reduced end section 127 and a shoulder 128 similar to the section 27 and the shoulder 28 of the core 24, and in addition thereto, the core 124 has a section 142 of a further reduced diameter extending from the section 127 and providing an annular shoulder 144. The pole piece 132 has an aperture 146 of a diameter slightly less than that'of the core section 142 for receiving it. After the coil is wound onto the bobbin and the core 124 placed within the bobbin, the assembled core and bobbin are placed on the core piece 122 and the section 142 of the core is pressed into the aperture 146 with the shoulder 144 of the core engaging the face of the pole piece to effect the securement of the core 124, the bobbin 10, and the pole piece in assembled relation to each other.

Although the pole piece is disclosed as L-shaped it will ,be understood that it may be fiat to support a pair of coils in parallel side-by-side relation to each other, or otherwise formed in accordance with the design of the desired coil assembly.

It is to be understood that the above-described arrangements are simply illustrative of the application of the principles of this invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. A coil mounting comprising:

a bobbin for supporting a coil and having a cylindrical tubular hub with outwardly projecting heads at opposite ends thereof and with :a plurality of lugs extending inwardly from the inner surface of the hub at one end thereof, said lugs having surfaces disposed substantially parallel to the axis of the hub and having shoulder forming surfaces disposed transversely of the axis;

a pole piece abutting said one end of said bobbin;

a cylindrical core fitting within said hub and having a a reduced end portion fitting between said lugs and providing an end surface in substantial alignment with the end surface of said bobbin and providing shoulders in overlying and 'abutitng engagement with said shoulder forming surfaces of the lugs; and

means for securing said core and said pole' piece to each other.

2. A coil mounting which comprises:

a bobbin having a tubular hub for supporting a coil 7 and provided with lugs extending inwardly from the inner surf-ace of said hub adjacent one end thereof;

a pole piece abutting said one end'of said hub and having an aperture therethrough; and

a core movable into said tubular hub and having a longitudinal first section conforming to and fitting within a portion of said hub and provided with shoulders disposed transversely of the axis of the core in abutting relation to said lugs, said core having a reduced second section extending longitudinal- -ly from said first section and fitting between said lugs and provided with a shoulder portion abutting said pole piece, said core having a further reduced third section extending longitudinally from said secend section and fitting within said aperture of said pole piece and secured thereby to said pole piece.

3; A coil mounting comprising:

a bobbin having a tubular hub with at least one lug extending inwardly from the inner surface of the hub at one end thereof and provided with a shoulder forming surface disposed transversely of the axis of said hub;

a pole piece abutting said one end of said hub;

a core movable axial-1y into said hub and having a first section conforming to and disposed in a portion of said hub and provided with surfaces disposed transversely of the axis of said core in engagement with said lug and having a reduced second section extending axially from said first section to the end of said core and laterally of said lug and provided with an end surface in abutting engagement with said pole piece; and

means for securing said core to said pole piece.

4. A co-il supporting structure comprising:

a support having a fiat surface;

a bobbin having a tubular hub with one end thereof engagable with said fiat surface of said support and provided with at least one lug extending inwardly from the inner surfaces of said hub adjacent said one end thereof;

a magnetic core movable axially into said tubular hub and having a longitudinal first portion conforming to and fitting within a major portion of said hub and provided with a shoulder at one end thereof disposed transversely of the axis of said core and said hub in abutting relation to said lug and having a reduced second portion extending longitudinally from said first portion to the end of said core and laterally of and adjacent to said lug and entirely within said hub and provided with an end surface in substantial alignment with said one end of said hub; and

means for securing said core to said support.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS France.

LEWIS H. MYERS, Primary Examiner.

D. I. BADER, T. J. KOZMA, Assistant Examiner. 

1. A COIL MOUNTING COMPRISING: A BOBBIN FOR SUPPORTING A COIL AND HAVING A CYLINDRICAL TUBULAR HUB WITH OUTWARDLY PROJECTING HEADS AT OPPOSITE ENDS THEREOF AND WITH A PLURALITY OF LUGS EXTENDING INWARDLY FROM THE INNER SURFACE OF THE HUB AT ONE END THEREOF, SAID LUGS HAVING SURFACES DISPOSED SUBSTANTIALLY PARALLEL TO THE AXIS OF THE HUB AND HAVING SHOULDER FORMING SURFACES DISPOSED TRANSVERSELY OF THE AXIS; A POLE PIECE ABUTTING SAID ONE END OF SAID BOBBIN; 